Point-of-entry and point-of-use water treatment arrangements for use in homes have been available for some time. Point-of use devices provide localized water treatment at a particular point within the home, such as filters that are attached to faucets. Point-of-entry devices are arranged near the home water-service entry point to provide whole-house water treatment. The point-of-entry devices in common use range from simple particulate filter elements, for filtering larger solid particles that are present in the incoming water, to filter elements that are intended to remove certain chemicals that are present in the incoming water, such as chlorine and organic contaminants. More recently, point-of-entry water treatment units have become available that incorporate ultraviolet lamps for disinfecting the water by exposing it to ultraviolet light in order to inactivate pathogens and other microorganisms that may be present in the incoming water.
Typically, separate treatment units are available for the removal of several undesirable contaminants that may be present in water for household use. It is therefore desirable to provide in a unitary vessel a treatment system for removing particulates and chemicals, and for disinfection of microorganisms. Desirably, such a vessel is of a relatively compact size and is one that is adaptable for retrofitting into existing home water plumbing systems.